abstract class people {
    float height;
    float weight;
    abstract void speak(String s);

    abstract void do_something();
    abstract int do_something(int n,int m);
}

class student extends people implements A{ //  子类继承父类，并同时实现接口

    //重写父类方法
    void speak(String s){
        System.out.println(s);
    }

    @Override
    int do_something(int n,int m) {
        System.out.println("简单加法");
        int q;
        q = n+m;
        return  q;
    }
    void do_something(){
        System.out.println("");
    }
    //重写接口方法
    public void  sing_dance_rap(){
        System.out.println("");
    }
    public void play_basketball(){
       System.out.println("");
   }
}
